Help - Mercury Grand Marquis won't start

T

Triple Black

Club Member
My daughters '92 Mercury Grand Marquis won't start. All seemed fine until one day when my wife got in, started it up and began to back up around a car parked behind. She started the several point turn, then stopped and turned it off and tried to find the keys to the car parked behind the MGM. Couldn't find them, so went back to the MGM. It only "kinda" turns over and never really sounds like it wants to start. A couple of neighbors think it could be something with the timing. Any ideas? The thought of the timing pin could be sheared. The auto gas shut off in the trunk has not been tripped. The gas was near Empty so I added a couple gallons.
 
Battery good? Take belt off to isolate the accessories from possible internal engine problems?
 
Beigg said:
Battery good? Take belt off to isolate the accessories from possible internal engine problems?
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The battery seems to be good. I swapped it out with a couple batteries from a boat and camper trailer with the same results. I also tried to jump start with another car. I haven't tried to take the belt off.
 
nitrouspete said:
id try spraying some ether into the throttle body....if she fires, you know you got a fuel problem.
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Thanks for the thoughts & tips. I am not a mechanic, so all your input is openly received. I am able to do a lot of things if you(all) tell me what to do. I am currently out of town, but I would like to verify if the valve you are talking about is the same that we checked. Sorry, I forgot about that. We did spray either into the throttle body and it still didn't' start.
 
its hard to diagnose a car over the internet and if you say your not a mechanic, that's gonna make it even harder. id say ur better off taking it to a shop if you need to get it done or find a friend who knows how to diagnose and have them look at it. just my $.02
 
Lake Orion. A friend of a neighbor said he could look at it. I am just not sure of how much it could cost. I am just trying to see if there is anything I can do that would fix or help prior to having someone more knowledgeable look at it.

Thoughts: I think I will take the valve covers off this weekend to see if there is anything in regards to the timing (tensioner, chain, pin, etc.)
 
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i bet that it has a plug window somehwere to take out and look at the chain to see if its still loving or broke. id look or ask around here...im not a 4.6 guy..sorry...
 
Fuel air spark. If it didn't start off starting fluid I'd check for spark. If you have air fuel and spark then I'd grab a timing light and see if timing is out to lunch.
 
Duke said:
Fuel air spark. If it didn't start off starting fluid I'd check for spark. If you have air fuel and spark then I'd grab a timing light and see if timing is out to lunch.
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I did check the plugs for spark this weekend. The plugs didn't look to new, so I bought new ones hoping that it could be a quick inexpensive fix. Could it be the coil pack (one or both)?

Speaking of the timing light, that is the direction my neighbors/friends are saying after they heard it (tensioner, chain, pin, everything that is inside and hard to get to w/out taking the whole front part of the engine off, etc.). It has two chains that run in a "V" shape. I thought a timing light was used on a belt. Will that still work with this car and the two chains? Is there a separate belt that is visible without taking the front half apart?
 
If you can identify at least a cam to be moving, then it's likely not internally fubared and just an electronic ignition issue
 
dave89iroc said:
Agreed, doesn't rule mechanical issues 100%, but odds are good its something else
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x2. If i'm remembering the year change correctly, this is the 4.6 2v similiar to what's in the stangs. The timing chains come down in a V and obviously attach at bottom middle. Coil packs are known for going kaputt on those cars randomly. There is no distributor to adjust timing. Any way to put a code scanner on it and see if it has thrown any codes? May just be as easy as no spark in a cylinder/cylinders. I'd pull the fuse for fuel pump so that you don't drown the cyclinders with gas, remove the plugs and check for spark at each plug.
 
CMYZ28 said:
x2. If i'm remembering the year change correctly, this is the 4.6 2v similiar to what's in the stangs. The timing chains come down in a V and obviously attach at bottom middle. Coil packs are known for going kaputt on those cars randomly. There is no distributor to adjust timing. Any way to put a code scanner on it and see if it has thrown any codes? May just be as easy as no spark in a cylinder/cylinders. I'd pull the fuse for fuel pump so that you don't drown the cyclinders with gas, remove the plugs and check for spark at each plug.
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I will remove the fuel pump fuse, pull each spark plug and test for spark. Question: If I am getting spark at every plug, is it possible the coil pack could still be bad, or is the coil pack fine if spark is at every plug? I would probably have to have it towed some place in order to check it with a code scanner. Would the auto parts stores have the scanner? If I tow it some place, I would like to have the option to leave it there and have it fixed if I exhaust my capabilities.
 
Well, I removed and checked 7 of the 8 spark plugs and they all had some spark. The other one is hidden and didn't take the time to remove it. Is it possible for the coil packs to be bad if there is some spark?
 
CMYZ28 said:
x2. If i'm remembering the year change correctly, this is the 4.6 2v similiar to what's in the stangs. The timing chains come down in a V and obviously attach at bottom middle. Coil packs are known for going kaputt on those cars randomly. There is no distributor to adjust timing. Any way to put a code scanner on it and see if it has thrown any codes? May just be as easy as no spark in a cylinder/cylinders. I'd pull the fuse for fuel pump so that you don't drown the cyclinders with gas, remove the plugs and check for spark at each plug.
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Thanks Nick.

UPDATE, UPDATE: Read all about it.

I bought and installed two new coil packs today. I turned it over, and the engine sounded more normal, like it was at least firing and trying to start. I hooked up a car to jump start it, AND VOILA, IT STARTED UP. But, when I let off the gas to let it idle, it stalls out and quits running. It does seem like it is running a little rough, not smooth. I know that all the plug wires are connected to the correct plug at the engine. I removed and replaced each plug from the coil pack one by one while holding the new coil pack in the same orientation as the old.
 
Triple Black said:
I hooked up a car to jump start it, AND VOILA, IT STARTED UP. But, when I let off the gas to let it idle, it stalls out and quits running. It does seem like it is running a little rough, not smooth. .
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Alt is toast based on that is my guess. Charge the battery up on a slow overnight trickle charge and take the alt off to have tested.
 
After letting it run for ~5 minutes, it was able to stay running at idle. Took it for a short drive in the neighborhood, and the check engine light came on. I think I am going to change the plug wires, oil, and fuel filter. Are there any tests that an auto parts store could run if I got it there? I also heard a clicking sound while it was running. Seem to be getting a little closer.
 
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